Windshield wiper



Aug. 19, 1952 J. v. s. DAHLGREN WINDSHIELD WIPER 12 Sheets-Sheet 1 Filed Oct. 15, 1945 l C@ .'14 f Aug- 19, 1952 J. v. s. DAHLGREN WINDSHIELD WIPER 12 Sheets-Sheet 2 Filed Oct. l5, 1945 J. V. S. DAHLGREN Aug. 19, 1952 WINDSHIELD WIPER 12 Sheets-Sheet 3 Filed Oct. 15, 1945 J. V. S. DAHLGREN Aug. 19, 1952 f wINDsHIELD WIPER l2 Sheets-Sheet 4 Filed 0G11. 15, 1945 J. V. S. DAHLGREN Aug. 19, 1.952

WINDSHIELD WIPER 12 Sheets-Sheet 5 Filed Oct. 15, 1945 Aug. 19, 1952 .1. v. s. DAHLGREN WINDSHIELD WIPER 12 Sheets-Sheet 6 Filed Oct. 15. 1945 ug. 19, 1952. J. v. s. DAHLGREN WINDSHIELD WIPER 12 Sheets-Sheet '7 Filed Oct. 15, 1945 Aug. 19, 1952 J. v. s. DAHLGREN WINDSHIELD WIPER Filed oct. 15, 1945 12 Sheets-Sheet 8 Aug. 19, 1952 -J. v. s. DAHLGREN WINDSHIELD WIPER 12 Sheets-Sheet 9 Filed Oct. l5, 1945 Wawy Aug. 19, 1952 J. v. s. DAHLGREN WINDSHIELD WIPER 12 Sheets-Sheet 10 Filed Oct. l5, 1945 v Aug. 19, 1952 J. v. s. DAHLGREN WINDSHIELD WIPER Filed Oct. 15, 1945 12 Sheet s-Sheet l1 I Mms.

im im 12 Sheets-Sheet l2 J. V. S. DAHLGREN Aug. 19, 1952 Filed oct. 15, 1945 Patented Aug. 19, 1952 WINDSHIELD WIrEa John Victor Stanley Dahlgren, Chicago, Ill., assignor to Stewart-Warner Corporation, Chicago, Ill., a corporation of Virginia Application October 15, 1945, Serial No. 622,238

27 Claims.

This invention relates to a windshield wiper and a drive mechanism therefor which is particularly designed to actuate the Wiper over a rectangular-shaped area of the Windshield.

One object of the invention is to provide a new and imp-roved windshield wiper arranged to clean a rectangular-shaped area of the windshield.

Another object of the invention is to provide a new and improved windshield wiper which includes mechanism for guiding the wiper blade over a rectangular-shaped area of the windshield, said mechanism including a minimum number of parts moving in the field of vision of the driver.

A further object of the invention is to provide anew and improved Windshield Wiper arranged to clean a rectangular-shaped area of the windshield and to be operated by a single actuating arm deriving its motion from a fulcrum point adjacent the edge of the windshield. i It is also an object of the invention to provide a new and improved windshield wiper and drive mechanism therefor, including means in the drive mechanism for deinitely locating the wiper and its carrying arm structure in a particular parking position at one edge of the windshi'eld'vvhen the wiper is not in use.

A further obj ect of the invention is torprovide a windshield wiper and improved drive mechanism therefor arranged to clean a rectangularshaped area of the windshield and designed to have suicient rigidity and mechanical eliciency to withstand exposure to air streams at high speeds.

Another object of the invention is to provide a Windshield wiper with drive mechanism adapted tooperate the wiping member at a sufciently high rate of oscillation to keep the windshield clean'during heavy rain and with a single blade operating on each half of the windshield.

More specifically, it is an object of the invention to provide a new and improved Windshield wiper mechanism arranged to traverse the Wiper horizontally across the windshield for cleaning a substantially rectangular area thereof and including a crank rarm having a rocking movement about a xed axis, an oscillating lever member actuated b-y said crank arm, and means for reciprocating the lever in the direction of its length to produce a substantially straight line motion of the end of the lever which carries the windshield wiper blade.

The-invention also includes means for connecting the blade to the oscillating lever and mechanism for maintaining the blade in a position substantiallyv parallel to itself throughout'its horizontal tra-verse of the windshield.

In addition to the foregoing it is an object of th'einvention to provide a new and improved windshield wiper mechanism with means for predetermining the position at which the mechanism will stop and so designed that at said position the wiper blade may be parked adjacent and parallel to one edge of the windshield.

Other objects and advantages of the'invention, will appear from the following description taken in connection with the drawings, in which:

Fig.1 is an elevation as viewed from the drivers seat, showing the upper portion of one-half of a vehicle windshield together with the wiper blade and the actuating arm therefor, which constitute a" portion of this invention;

Fig. la is a continuation of Fig. 1, showing in elevation the lower portion of the windshield, on a somewhat larger scalatogether with driving mechanism for the windshield wiper; y

Fig. 2 is an elevational view similar to Fig. l but showingy the windshield wiper blade and its carrying arm in upright position at approximately the middle of its range across the windshield; f

Fig. 2a. is a continuation of Fig. 2 on a slightly larger scale,` showing'the parts of Vthe operating mechanism in positions corresponding to the position of the wiperblade in Fig. 2;

Fig. 3 is an elevational View similar to Figs; 1 and 2 but sho-wing the wiper blade and its carrying arm at the limit of its range of movement opposite to that illustrated in Fig. 1;

Fig. 3c is a continuation of Fig. 3 showing the lower portion of the windshield on a larger scale together with parts of the operating mechanism positioned to correspond with the position of the wiper blade in Fig. 3;

Fig. 4 is a view similar to Figs. la.,y 2a, and 3a., but showing the control switch moved to the off position and showing the parking control lever adjusted for determining the position at which the wiper blade will be arrested and parked;

Fig. 5 is a view similar to Fig. 4, but showing the wiper blade and its carrying arm disposed in parking position;

. Fig. 6 is a vertical longitudinal section taken substantially as indicated at line B--S on Fig. 2a;

Fig. 6a isa continuation of Fig. 6 and illustrates the windshield wiper and the upper end of its carrying arm structure;

Fig. 7 is a detail sectional view taken as indicated at linev T--l on Fig. 2a.;

Fig. S is an enlarged horizontal sectional view taken as indicated at line 8--3 on Fig. 6;

Fig'. 9 is a fragmentary sectional Vview on an enlarged scale to illustrate certain details ofthe mechanism shown in Fig. 6;

Fig. 10 is a sectional detail viewv showing'the bearing structure for the lowerend of the oscillating lever which transmits motion to the windshieldwiper;

Fig. 11 is a detail section at a vertical plane taken substantially as indicated at line I l-H on l2 is an enlarged fragmentary detail section illustrating the dlsengageable connection between the driving segment and the lever which determines the parking position of the wiper blades;

Fig. 13 is a fragmentary detail sectional View taken at line I3-I3 on Fig. 7;

Fig. 14 is an enlarged detail section taken as indicated at line I4--I4 on Fig. 8; I Y

Fig. 15 is an enlarged detail section taken as indicated amine Is-ison Figs;

Fig. 16 is a transverse detail section at line IEB-I6 on Fig. 6a;

Fig. 17 is a transverse detail section at line I'I-I'I onFig. 6;

Fig. 18 is a detail View taken substantially as indicated at line I8-I8 on Fig. 15;

Fig. 19 is an enlarged axial sectional View of the combined main switch, and control mechanism being taken as indicated at line Ill- I9 on Fig. la;

Fig. 20 is a face View of the control mechanism as indicated at line 29-29 on Fig. 19 and including a wiring diagram.

In a windshield wiper it is of course desirable that the wiper blade traverse as large an area as possible of the windshield or window which the driver or pilot of the vehicle depends upon for his View. In an automobile, this window usually is rectangular in shape, but in most cases it is convenient to provide actuating power for a wiper blade in the form of an oscillating shaft and to transmit motion from such shaft to the blade by means of a swinging arm. Normally, this would actuate the blade in an arcuate path so that only a segmental portion or curved strip of the windshield area would be traversed. The present invention,V however, provides a mechanism whereby an oscillating lever arm swinging about a single axis causes the wiper blade to move along a substantially straight path so as to sweep a rectangular area of the windshield. In Fig. l, the upper portion of one-half of the Windshield is shown at I0 with its marginal frame II engaging one side and the top, and with a verticalframe member I2 which may be understood as disposed at the middle of the windshield at the inner edge of the portion Ill. If it is desired to keep both halves of the windshield clean,

the mechanism of this invention may be duplicated at the right hand side, but for purposes of illustration and description the drawings show only the mechanism for cleaning the portion l0 in front of the drivers seat. The wiper blade I4 is shown in dotted lines in this view attached to a carrying head I6 at the outer end of a shaft I8 which extends from a tubular carrying arm 2B. 4'Asshown in Fig. la, which includes the lower portion of the windshield section ID and the bottom member I3 of its frame, the tubular arm 2i) is seen extending rigidly from a cylindrical case 22 having a fixed circular back wall 24 which is secured by screws 25, 26 to a mounting plate 28 supported in any convenient manner in the vehicle and in a plane slightly forward of the plane of the windshield Il. The cylindrical case 22 is mounted to oscillate about its own axis and the shaft is arranged to slide through the case 22 along a diameter thereof as will be explained more fully hereinafter. The lower end of the shaft I3 is connected by a'crank pin 3B to the end of the crank arm 32 which is attached to a gear wheel 34 for oscillation therewith about the axis of said gear. The gear wheel 34 is journalled at 36 on the mounting plate 28 and meshes in one direction thus serves to oscillate the gear segment 38 back and forth so that it drives the gear 34 first in one' direction and then in the opposite direction'. In the particular design shown,V the crank arm 32 attached to the gear 34 is thus swung through a total angle of about 264, which sweeps below the axis of the gear 34; 117 of this range is disposed ai; one side of the vertical radius through said axis and about 147 is disposed at the other side because it is found desirable to locate the axis ofthe journal bearing 36, as indicated in Fig. l, somewhat nearer to one end than to the other end of the windshield panel IG. In some cases it may be possible to arrange this axis exactly at the middle of the range of travel of the windshield wiper and to operate the crank arm through the same angle at both sides of the center.

As shown in Fig. 2c, the arm 32 extends vertically downward from the journal axis 36 when the shaft I8 and its carrying arm 20 extend vertically upward from the axis of the case 22, said axis being disposed directly above the journal axis 3E. Fig. 6 shows some of the details of this structure in the positions in which they are illustrated in Fig. 2a.. The mounting plate 28 is offset at 29 and below this oiset it supports the journal stud 36 on which the gear wheel 34 is mounted.

If the crank pin 3B were xed at the outer end of the arm 32, the resulting motion of the upper end of the shaft I 8, as indicated by the dotted line X-in Figs. 1, 2, and 3, would not approximate a straight line as closely as necessary for the purpose of this device; accordingly, this movement is modified slightly by providing a xed cam 52 secured to the inner end of the journal stud 36. The crank pin 3G is mounted in a slot 54 extending longitudinally in the arm 32, and a link 56 connects the pin 30 with a stud 58 which is slidable in a second slot 60 in the arm 32 and `carries a roller 62 engageable with the periphery of the cam 52. A spring 64, extending between the crank pin 30 and an anchor prong 66 struck out of the crank arm 32, holds the roller 52 yieldingly in contact with the cam 52, causing it to follow the contour thereof` as the arm 32 swings through its range so that instead of moving in a strictly circular arc 1G, the crank pin 30 follows the path 'I2 and the outer end of the shaft I8 moves along in a straight line as indicated at Y in Figs. 1, 2, and 3.

Referring to Fig. 6, it will be seen that the case 22 is journalled for rotation about its axis, being rotatably engaged with the circular wall 24. A spindle .T4 staked to the case 22 extends axially through it and a reduced portion of the spindle bears in a recess 'I6 in the wall 24. A headed screw 'I8 secured in the end of the spindle 14 anchors the case 22 rotatively to its end wall 24. Within the casing 22 the shaft I8 which is of square cross section extends slidably through a square opening in a bevel gear pinion and said pinion is fixedly journalled in a bracket plate 82 which embraces and extends from the spindle I4. As thus located, they pinion 8D meshes with bevel gear teeth 84 formed on the inner face of the fixed wall 213 for a purpose which will be explained hereinafter. The shaft I8 is in. two parts and includes the.. portion |8a'which extendsthrough the tubular arm 20 and is journalled in the outer end thereof at 86 (see Fig. 6em-.w The part: |'8 'and the part A|.8a are connected by a hinge pivot 88 and said 'parts are normallyaligned except when folded at this pi-vot toplace the wiper blader and its adjacent parts in'parking position. Asthe angular position of the shaft `|8 is changed by the rotation of the crankarm 32V and its crank .pin 30, theY case 22 turns .through a' correspondingangle because the bracket-62r `which Aincludes -a portion embracing the spindle 14 also includes aradially extending clutch plate portion 90 with which a clutchpin 92is normally engaged. Said clutch pin 92 yis carried by a yoke 94 secured by a' pivot 96 to the spindle 14 and the clutch pin 92 normallyvoccupies an aperture 98 in the plate 90. Thus as thepinion 80 follows the'swinging movement of the `shaft |6, it is controlled by the journalling of its bracket plate 82 on the spindle 14v and .swings .about the axis of said spindle. 'I'his movement of the bracket 82 causes its clutchvplate portion`90 to swing about the axis` of thespindle 14 and to rotate the spindle with it by virtue ofthe interconnection between the plate 90 and the spindle 14 provided by the clutch pini 92 .and the yoke l94. As the spindle 14 swings `about axis, it carries with it the case .2 2--agnd' the tubular 'arm 20-in which the outerportion Hitt of the shaft I8 is supported and journalled. yThus, the oscillating motion of the gear-34 causes an :oscillating motion of the' shaft I .and of the case 22 to which it extends.

tube |10. of square cross section extending rigidly from, the case 22 in parallely relation to the tubular. arm 20. YBearing balls l2 are retained in individual recesses near the outer end of the tubelll and'in engagement with the surfaces of the' guidebar |08, and near the inner end of I the tubevll0. the bearing balls ||4 are disposed in :recesses in the bar |08 and in bearing engagement with the -wall of the tube H0. The outer end oflthe bar l|08 is .bent at right angles and includes a reduced cylindrical portion ||6 with which the end wall ||8`of the head |00 is rotatably engaged. The bent portion of the bar |03 fits betweenicheeks |06 cast in the head member |00. A locking washer |20 fitted in a groove in the part |I6 retains said en d wall thereon; This''arrangement permits the head |00 tomove through a limited distance toward and 'fromthe outer ends of the tubesr 20 and J in response to the longitudinal movement of the shaft |8 which results from` its connection withY the crank pin 30 asthevlatter is rotated about the axis 36 of the gear 34 and is shifted along the crankarm 32 by the cam 52. The'shaftv I8 is of square cross section throughoutmostof its length and at the portion which nts sudabiy in the bevel gear pinion su, but at its lower end it is turned down to form a journal |22, and a bearing |24 is provided therefor on theend of the pivot or crank pin 30 as seen inFigs. 9 and 10. The meshing of thepinion 80 with the teeth 84 causes the pinion to rotate as the shaft I8 swings about the axis of the.

|02 of' the lpart I8 'turns with it as the shaft |8a and its enclosing tube Aswing vthrough the angle of yoperation vwhich causes the wiper blade.

to traversethe windshield panel I0. Theratios of these gear connectionsare so calculated as to turn the wiper blade |4 with respect tothe head |00 just enough so that throughout the travel of the wiper blade across the windshield it ismaintained in a substantially vertical .po-

sitionparallel at all times to its original position; and since the path of travel of the axis of the head |00I as rectified by the operation of the cam. 52 is a straight linegY, as already explained, the wiper blade operates to clear a rectangular field or area of the windshield panel l0, sweeping back and `forth across thisv rectangular area as the motor 42 continues to oscillate the gear segment 38 and the gear wheel 34.

The motor 42 is operated from a current source indicated at on Fig. 20, and is controlled by a switch mechanism lwhich. includes a low speed contact |32 in circuit with a resistance |34., a.

high speed contact |36 and a rotatablecon'tact arm' |30 operable by a switch handle |40. lThe handle includes an indicator point |42 which traverses a dial plate |43 `with markings oiff high and lo-w, as shown in Fig. 20. A limit switch |44 is included in the motor circuit and is provided with an actuating button |46 operable as hereinafter described. In addition to controlling the operation of the motor 42, the switch handle |l actua-tes mechanismf'which automatically causes the shaft |8, maand the carrying arm 20 to be arrested at vertical position, as shown in Fig. 4, and then automatically swings the arm 20 and shaft |8a to thehorizontalparking position illustrated in Fig. 5. When handle |49 is moved to the off position, itrotatesa cam cylinder |46 to a position at which its helical cam slot |50 shifts the follower |52 on a plunger |54 in a `guide cylinder |56A whicvhis carried by the switch casing |50. The plunger Y|54 is attached to one end of a Bowden wire '|607 eX- tending through a guide tube |62 to a second guide cylinder |64 which is secured rigidly to one end of a lever arm |56. Within the cylinder |64 a hollow plunger |68 encloses a spring |10 which is disposed between a piston head |12, captive within the plunger 68 and the head |14 of a clutch pin |16 mountedslidably within the cylinder |64. When the Bowden wire is advanced by the turning of the handle |40to the off position, it compresses the spring |10 and forces .the end of the clutch pin |16 against the face of the -gear segment 38 so that when a hole |13 in the gear 38 registers with the clutch pin |16, the latter is snapped into the hole |18 as shown in Fig. l2 and thus interlocks the lever into the slot '188, as seen in Fig. 12. Theleve'r arm 166 thus moves to the position shown in Fig. 4 at which it depresses the button 146 of the limit switch 144, opening `the circuit of the` motor 42 and arrestingoperation of the mechanismwith the shaft 18a and its v'eri-closing tubular arm20 in upright position. l

`The lever arm 188 is secured rigidly to one end of a shaft 184 journalled in a bearing bushing .185 which vis supported in the mounting bracket 28 and upon which the gear segment 38 is rotatably mounted The other end of the shaft r11114 carries a leverarm 186 which thus swings in unison with thel arm 166,` and when the latter moves to the position shown in Fig. 4 to actuate the limit switch 144, the arm 186 operates to tension a spring A188 Vwhich connects the arm 186 with a leverarm 198 extending downwardly from the case `22. l

As shown in Fig. l5,v the lever arm 198 is connected by a pivot 192 to a plate 194 inside the case 22, said plate being rotatably -carried'by the spindle '14` but normally held against rotation by a spring pressed dog 196, more clearly seenv in Fig.' 8. One end of the dog 196 engages'a notch 19-8 in the plate-194 and -at the other end the 'dog is pi'voted to a lug 288 of a bracket plate 282 carried on the-spindle '14 and anchored by engagement with an extension 284 of one of the fastening screws 26. The lever 198 includes an offset portion 288 which is bent past the plane of a wing portion 288 of the yoke 94 so that the initial movement of the lever 198, in response totension of the spring 188, swings the bent or o iset part 28E of the lever into camming engagement with the wing 208 and rocks the yoke 94 through a small angle about its pivot 96. The wing portion 208 of the yoke carries the clutch pin 92 as seen in Fig. 8, and the clutch pin is held normally in engagement with the plate 98 by means of a spring 218 reacting against the plate 194. The camming action of the part 288 against the wing 288 swings the yoke 94 sufliciently to withdraw the clutch pin 92 from the :plate 911,l thus disconnecting theyoke 94. from thebracket 99 and permitting rotationV of the spindle '14 and case 22 relative to the bracket plate 99 and gear pinion 881 with which it is inter-engaged. As one end of the clutch pin 92 is thus withdrawn from the plate 98, the other end operates to force the dog 198 out' of the notch 198', thus leaving the plate 194 free to turn with respect to the bracket plate 282 and the fined 4wall 24 of the case 22. The lever arm 198 has a lug 212 which engages a prong 214 of the :plate 194 after the initial movement of the arm 198 has rocked the yoke 94 and withdrawn the clutch pin 92 from the plate 98 as just described. Further movement of the arm'198 thus carries with it the plate 194 and the yoke 94 which has become interlocked with the plate 194 by engagement of the clutch pin in the notch 198. The tension set up in the spring 188 is suiiicient to swing the arm 190 through an angle of about 90, [thus causing the yoke 94 and spindle '14 attached thereto to turn through a similar angle, rotating the case 22 through 90 and swinging the carrying arm 211k from its vertical position, as seen'in Fig. 4, to horizontal parking position, as shown in Fig. 5. When this occurs, the coupling pivot 88 between the shaft 18 and the shaft 18a is positioned as shown in Figs. 6 and 14 at the axis of the case 22 and spindle '14 so that as the case 22 and carrying arm 28 are rotated through the 90 angle, the upper section 18a of the' shaft swings freelyV about this pivot A88 and' assumes its horizontal parking position andv there is no strain on the connectedl parts. Since the wiper blade 14 is maintained in a vertical position throughoutits travel across the windshield and. is controlled positively by the position of the wall 118 of the head-188, the blade will be disposed in its vertical position parallel to the tubular arm 28'when`the parking operation'is com'- menced, and :will remain parallel tothe arm 28 as the latter swings to horizontal position. l'

'To re-start operation ofthe-'wiper blade, the control handle 149'is swung to position its indicator-142 either at the -high mark of the dial or atthe low mark, so that operative contact is established for the circuit of the motor 42. 'I'he circuit will `remain open as long as thelimit switch 144 stays open, but movement of the' handle 148 away from the off position will rotate the cam cylinder 148 vand cause the follower 152 and its' plunger 154 to be retracted inthe cylinder 156 to the position vshown in Fig. 19. This will retract the Bowden wire 168 and withdraw the hollow plunger 188 to the position shown in dotted lines in Fig. 12, and in full lines in Fig. 7, at the same time withdrawing the clutch pin 116 from the hole 118 in the gear segment 38. As shown in Fig. 5, the movement of the parts to parking position under the retractile force of spring v188 results in tensioningthe spring 216 which is also connected atene end to lever arm `and is anchored at the other end to a` laterally extending arm 218 attached to the mounting plate 28. Upon withdrawal of the clutch pin 1'16 from the segment 38 the tension in the spring 216 will oper.- ate to swing the arm 198 back to its normal position and this movement operating through the spring 188 will initiate the movement of the lever arms 186 and 166 toward their original position, thus withdrawing the lever 168 from the limit switch button 146 and permitting the limit switch 144 to close, whereupon the motor circuit is reestablished.

YThe contraction of the spring 216 is accompanied by very little extension ofthe spring 188 since the lever arm 166 is free to return to the opposite endcf the arcuate slot 180, and as .the spring 216 contracts it swings the lever arm 198 back to its original position. This movement first swings the plate -1 94 back toward its original posi-v tion, carrying with it the yoke 94, which is interlocked with the plate 194 by engagement vof the small end ofthe pin 92 in the notch 1-98. The movement of the yoke 94 rotates the spindle '14 and the case 22 to return the arm 28 and the shaft 18a to vertical positions. In the initial portion of this return movement, however, the arm 198 will swingabout its pivot 182 through a small anglesufcient to bring its lug 220 into engage-r ment with the edge of the plate V194 asshown in Fig. 15, and in this position the offset or cam portion 286 of the arm 190 will be withdrawn from the path of the wing portion 208 vof the yoke 94 so that the spring 218 can return the clutch pin 92 into engagement with the bracket plate-98. When the tubular arm 20 and the shaft 18a reach the upright position shown in Fig. 2a, the spring 218 moves the clutch pin 92 out of the notch |98 in the plate19 4 and into the hole 98 in the bracket plate 98. Thereafter the wiper blade will be actuated by oscillation of the gear 34 and the arm 32 to which the shaft 18 is connected.

It will be recognized that the shaft 18 and its extensions 18a perform a four-fold function.` Since the outer end ofthe shaft 18a is anchored to the wsu Hs of the head me by its bearing engagement in the bridge or web 222 of the head `i 0D as seen in Fig. 1l, the shaft may be considered as an arm which carries the wiper blade. The upper portion of the shaft constitutes a driving arm which extends radially from the casing 22 for oscillation with it while the lower portion of the shaft serves as means to oscillate the casing 22 and the wiper carrying arm about the fixed axis cf the casing. In addition, the shaft i8, ISa

.being slidable through the casing 22 4and being .thus reciprocated by the motion of the crank arm 32 serves to vary the distance between the axis of oscillation and the connectiony ofthe blade to the arm which carries it, thus insuring movel ment of the blade in a substantially straight path across the windshield. A further function of the shaft i3, lila is performed as it is rotated by meshing of thebevel gear B with the teeth lill. so that the shaft shall cause the wiper blade to turn on the pivotal bearing l i6 and maintain its vertical position throughout its travel across the windshield. In folding to parking position the shaft i8, 58a may be even considered as performing a fifth function; namely, retaining thewper blade in alignment with the shaft i8a as it is swung to parking position; this results from the hinged connection between the parts la and l8a at 88 which must be axially aligned with the spindle lil to permit the folding movement. This means that the rotation of the shaftA i8 by its bevel gear 80 must be so calculated as to bring the hinge pivot 88 into alignment with the spindle axis at the instant when it arrives at the level of this axis; then when the part 18a is folded about the vhinge pivot, neither section of theY shaft can rotate and the part t8 may be considered as serving to lock'the part Isa so that the wiper blade cannot rotate during the parking movement. The member |08 acts mainly as a steady arm for the head |00 and rigidity is further added to the mechanism by the tubes 20 and I l0 anchored in the casing 22 and swinging with it as it oscillates.

While there is shown and described herein certain structure illustrating the invention, it is to be understood that the invention is not limited thereto or thereby but may assume numerous other forms and includes all modifications, variations and equivalents coming within the scope of the following claims.

I claim:

1. In a windshield wiper, a wiper blade, an oscillating hub having a diametral aperture, a driving arm slidably extending through the aperture in the hub with the blade attached to said arm, and means for vsliding said arm through said hub as it oscillates to vary the distance between the axis of the hub and the point of attachment of the arm to the Wiper blade for causing said blade to travel in a substantially straight path across the windshield.

2. In a windshield wiper, a wiper blade, a hub mounted for oscillation about a xed axis, the hub having a diametral aperture, a driving arm extending through the aperture in the hub for oscillation therewith and slidable through said aperture, means securing the wiper blade to one end of said driving arm, a crank arm journalled to oscillate about an axis parallel to the axis of said hub member, a crank pin connecting the other end of said driving arm to said crank arm,

and means to oscillate said crank arm for simultaneously oscillating said driving arm about the axis of the hub and sliding said driving arm through said hub.

-means securing the wiper blade to said driving arm, a crank arm journalled to oscillate about an axis parallel to the axis of said member and operatively connected to said driving arm,v and means automatically varying the effective length of said crank arm as it oscillates.

4- In @windshield wiper, a wiper blade, a member mounted for oscillation about alxed axis, a driving arm-extending radially from said member for oscillation therewith and slidable through said member, means securing the wiper blade to said drvingiarm, agcrank arm journalled to oscillate aboutv an axis parallel to the axis of said member, Aa crank pin connecting said driving armto the crank arm, and Vmeans automatically shifting said pin along the crank arm as it oscillates. Y

5. In a windshield wiper, a wiper blade, a member mounted for oscillation about a fixed axis, a driving arm extending radially from said member for oscillation therewith and slidable through said member, means securing kthe wiper blade to Vsaid driving arm, a crank arm journalled to oscillate about an axis parallel to the axis of said member, a crank pin connecting said driving arm to the crank arm, means supportingsaid crank pin on the crank arm with capacity for adjustment toward and from the axis of oscillation of said arm, a xed cam, and a follower connected to said crank pin and engaging the cam for effecting said adjustment of the crankpin as the crank arm yoscillates.

6. In a Windshield wiper, a wiper blade, a member mounted for oscillation about a fixed axis, a driving arm extending radially from said memb er for oscillation therewith and slidable through said member, means securing the wiper blade to said driving arm, a crank arm journalled to oscillate about an axis parallel to the axis of said member, said crank arm having a slot, a crank pin engaged in said slot and connecting the crank arm to the driving arm, a .cam and a follower therefor, a link supporting said crank pin in said slot and connected to saidfollower,

. outer end of said guide bar and supporting the wiper blade, bevel gear teeth on saidl bracket, a shaft extending through said shell parallel to the guide bar and journalled for rotation about its own axis, meansv to oscillate the shaft about the axis .of the shell and means to oscillate the shell therewith, a bevel gear pinion on said shaft, bevel gear teeth on the fixed end wall ofthe shell meshing with the pinion and causing the shaft to rotate as it oscillates, and a bevel gear carried by the outer end of the shaft in mesh with bevel gear teeth on said bracket, whereby the bracket and the wiper blade are turnedv relatiyety tothe guide bar by said rotation of the s a conoce 4guide bar being slidable radially toward and from the shell, the means which oscillates the shaft including a crank arm oscillating about an axis parallel to that of the shell with a journal bearing for one end of the shaft pivoted to said crank arm, a journal bearing for the other end of the shaft xed on said bracket, and shoulder means by which the shaft engages both said bearings, whereby the shaft is simultaneously oscillated and reciprocated by the crank arm to move the wiper blade in a substantially straight path across the Windshield.

l0. In a windshield wiper, a wiper blade, an oscillating member, a driving arm extending radially from said member with the blade attached to said arm, means for sliding said arm through said member as it oscillates to vary the distance between the axis of oscillation and the point of attachment of the arm to the wiper blade, said arm having a hinge joint intermediate its ends, and means for arresting said arm with the axis of its hinge joint at the axis of said oscillating member to permit the blade-carrying portion of the arm to be swung about said axis into a parking position. n

11. In a Windshield wiper, a wiper blade, an oscillating member mounted for oscillation about an axis adjacent one side of a windshield, a driving arm extending radially from said member, means pivotally securing the blade to said arm, means automatically turning said blade upon its pivot axis to hold it parallel to an initial upright position throughout its travel across the Windshield, means for arresting the arm in upright position in alignment with the blade, and means to retain said parts in alignment as they are swung about the axis oi oscillation into a parking position adjacent one side of the windshield.

12. In a windshield wiper, a Wiper blade, a member mounted for oscillation about an axis adjacent one side of the Windshield, a driving arm extending radially from said member with the blade attached thereto, a second arm extending radially from said member, means for oscillating said second arm about the said axis, clutch' means normally connecting said second arm to said member for oscillating said member and the driving arm with the blade attached to it, and means for disengaging said clutch means and arresting the oscillating means permitting said member and said driving arm to be swung about said axis to bring the driving arm into alignment with said side of the windshield in its parking position.

13. In the combination defined in claim 12, a parking lever and a parking spring attached at one end to said lever, a tensioning lever attached to the other end of said spring, means operable at will to connect said tensioning lever with the means which oscillates said second arm for causing said lever to tension the parking spring, and means automatically locking said member and the driving arm to the parking lever upon disengagement of aforesaid clutch means, whereby the tensioned parking spring acts 12 i through the parking lever to swing the driving' arm into its parking position.

14. In the combination deiined in claim l2, a parking lever and a parking spring attached at one end to said lever, means connected to the other end of said spring and operable at -will for tensioning it, said means for disengaging the clutch means including a shifter actuated by said parking lever when said spring is tensioned,

means also actuated by said lever to lock the leverto said member and the driving arm as said clutch is disengaged, whereby further movement of the parking lever by said tensioned spring swings the driving arm into its parking position.

15. In the combination defined in claim 12, said wiper blade being pivotally attached to the driving arm, means automatically turning said blade about said pivotal connection and changing itsangular relation to the driving arm as it is carried across the windshield thereby, said means for arresting the oscillating means being eiective only when the blade is aligned with said driving arm, and means maintaining said alignment when the driving arm is swung into parking position.

16. In a windshield wiper, a wiper blade, a member mounted for oscillation about an axis adjacent a horizontal side of the windshield, a driving arm extending radially from said member with the blade pivotally attached thereto, a second arm extending radially from said member, means for oscillating said second arm about the said axis, clutch means normally connecting said second arm to said member for oscillating said member and the driving arm with the blade attached thereto, means causing said driving arm to turn about its own axis as it oscillates, gearing transmitting said turning movement to the blade at a rate to maintain it in vertical position throughoutv its travel across the Windshield, whereby said blade is aligned with the driving arm when the latter is upright, and means operable automatically to disengage the clutch means and arrest the oscillating means when said driving arm is in upright position, permitting the driving arm to be swung with said member into horizontal lparking position at the side of the Windshield with the wiper blade aligned with the driving arm.

17. In the combination dened in claim 16, means locking said driving arm and the wiper blade against rotation when said arm is swung to parking position.

18. In the combination defined in claim 12, the means for oscillating said second arm including an electric motor and a rocking member driven thereby, a switch for said motor and a trip member for said switch, said wiper blade being pivotally attached to the driving arm, means automatically turning said blade about said pivotal connection and changing its angular relation to the driving arm as it is carried across the windshield thereby, said means for arresting the oscillating means including a part engageable at will with said rocking member to move with it and operative to engage'the trip member for opening the switch when the wiper blade is aligned with said driving arm.

19. In the combination defined in claim 12, the means for oscillating said second arm including an electric motor and a rocking member driven thereby, said wiper blade being pivotally attached to the driving arm1 means automatically turning said blade about said pivotal connection and changing its angular relation to the driving arm as itislcarried across the windshield thereby, said' means for disengaging the. clutch -means including a shifter for said. clutch means, `a lever to actuate said shiftena spring connected atone end to said lever, a lever arm connected to the otherend of said spring, means operable at 'will to interlock said leverarm with said rocking an electric motor and a rocking memberV driven thereby, a switch for. said motor and a trip member for said switch, said wiper blade being pivotally attached to the driving` arm,

`means automatically turning said bladeabout said pivotal connection and changing its angular relation to-the driving arm as itis carried across 'the windshield thereby, said means for disengaging the clutch means including a shifter forsaid clutch means, a lever to actuate said shifter, a spring connected at one en d to said lever, a lever arm connected to the otherend of said spring,

means operable at will to interlock said lever arm with said rocking member to cause the lever to be rocked thereby and to tension said spring, the spring tension actuating the shifter lever to disengage said clutch means when the wiper blade is aligned with said driving arm, said trip member being positioned for actuation by said lever -arm substantially simultaneously with the disengagement of the clutch means.

21. In the combination deined in claim 12, a parking lever and a parking spring attached at one end to said lever, a tensioning lever attached to the other end of said spring, means operable at will to connect said tensioning lever with the means which oscillates said second arm for causing said lever to tension the parking spring, and means automatically locking said member and the driving arm to the parking lever upon disengagement of aforesaid clutch means, whereby the tensioned parking spring acts through the parking lever to swing the driving arm into parking position, together with a return spring also attached to the parking lever and tensioned by the movement of said lever which swings the driving arm to parking position, and manually operable means for releasing the tensioning lever from its connection with the means for oscillating said second arm, permitting. said return spring to swing the driving arm from parking position into operative position.

22. In the combination defined in claim 12, a parking lever and a parking spring attached at one end to said lever, a tensioning lever attached to the other end of said spring, means operable at will to connect said tensioning lever with the means which oscillates said second arm for causing said lever to tension the parking spring, and means automatically locking said member and the driving arm to the parking lever upon disengagement of aforesaid clutch means, whereby the tensioned parking spring acts through the parking lever to swing the driving arm into its parking position, together with a return spring also attached to the parking lever and tensioned by the movement of said lever which swings the driving arm to parking position, and manually operable means for releasing the tensioning lever from its connection with the means for oscillating said second arm, permitting said return spring `tosiving therdriving arm from/parking position into 'operative Iposition. .such `release of the tensioning leveroperating vto a energize Asaid means -for oscillating the second arm, thus setting thewiper mechanism in motion. A i

23. In awindshield wiper, a wiper 'blade-a member mounted for. oscillation about an axis adjacent one side of a windshield, a drivingarm extending radially from said member with ythe wiper blade attachedto isaidi arm, means for oscillating said memberincluding an electrici motor and. a rocking member driven thereby. a switch for said motor and a trip memberdepressibleifor. opening saidswitch, a lever arm, means operable at Lwill toengage Vsaid lever` arm with said rocking member, ,said lever being swung by said rocking member to depress v'the trip member to stop the .motor with said driving arm at a predetermined position, and aspring .attachedto said levenarmand tensioned, by .the movement thereof which actuates the trip'member, said `means vengaging .the .lever with .the rocking memberbeing also operable at willto disengage said :lever-.from the rocking member, Vwhereupon the spring withdraws the lever .from

the trip member., permitting the 'switch to close and causing the motor to resume actuation of the windshield wiper.

24. In a cleaner for the windshield of an automotive vehicle or the like, an elongated drive member oscillatable and movable in an endwise direction, a wiper blade adjacent one end of said drive member, means for oscillating said drive member and for moving the same in an endwise direction, and guide means intermediate the ends of said drive member to guide movement thereof including a member oscillatable upon a xed axis located on one side of said windshield to constrain said drive member for oscillation at said intermediate point upon said fixed axis, and means spaced from said intermediate part of said drive member and rockable with said oscillatable member for guiding endwise movement of the drive member.

25. In a windshield cleaner, an oscillatable member, a iixed support for said oscillatable member, a gear, means to x said gear for oscillation with said oscillatable member and for rotation on its own axis, an elongated drive member, said drive member and gear being fixed against relative rotation and movable relatively in a direction axially of the gear, a wiper rotatably supported adjacent the outer end of said drive member, means to oscillate said drive member for moving the wiper over said windshield and to move the same in an endwise direction for maintaining the end of said drive member at which said wiper is secured on a straight line as it moves over the windshield,` said gear and the means to x the same against oscillation relative to the oscillatable member forming a driving connection between the latter and said drive member, gear teeth on said iixed support at a position to be engaged by said gear for causing said drive member to be turned upon its axis when said oscillatable member and gear are oscillated, and means including a gear train to turn said wiper when the drive member is turned.

26. In a windshield wiper, an elongated drive member oscillatable and movable in an endwise direction, said member having a hinge joint intermediate its ends, a wiper blade operated by said drive member, means to guide movement of said drive member including a member oscillatable upon a fixed axis, means for oscillating said drive .member and for moving the same endwise to carry-the axis of said hinge joint across said fixed axis, means including clutch means operatively to connect said drive member and oscillatable member so that said drive member is constrained for oscillatory movement upon said xed axis, control means including means operable at will and means rendered effective automatically upon operation of the means operable Aat will to operate 'said clutch for disconnecting said drive member and oscillatable member when the axis of the joint in said drive member coincides with the axis of said oscillatable member whereby one end of said drive member and said oscillatable member are freed for rocking movement upon said xed axis independently of the other end of said drive member` 27. In a windshield wiper for cleaning a substantially rectangular area of a windshield, a hub mounted for oscillation about a iixed axis, a driving mechanism to oscillate the hub, iirst and second generalyeparallel arms extending radially from the hub for oscillation therewith,

means on the hub telescopically engaging the arms to provide for radial extension of the latter, a wiper blade pivotally connected to the outer end of the rst arm, means to rotate the secondarm about its own longitudinal axis as .the arms oscillate, gearing forming a driving connectionbetween the outer end of the second arm and the wiper blade to turn the latter to maintain the latter parallel to its initial positionas the arms oscillate, and means forming part of the driving mechanism engaging one of the arms to shift the latter radially for moving the wiper blade in a substantially straight line across the windshield as the arms oscillate.

JOHN VICTOR STANLEY DAHLGREN.

REFERENCES CITED A The following references are of record in the file of this patent:

UNITED STATES PATENTS 

